PAI-1 emerged recently as a critical link between the epithelium and inflammation, which showed elevated mucosal gene expression in patients with IBD who did not respond to anti-TNF biologic therapy.11 The present study demonstrated that the serum, mucosal, and faecal PAI-1 concentration is selectively elevated in IBD patients showing clinical and endoscopic activity but not in other organic gastrointestinal diseases, and decreased significantly upon successful therapy in responders. The gene discussed is SERPINE1; the disease is inflammatory bowel disease.